Hot melt compositions

ABSTRACT

HOT MELT COMPOSITIONS CONTAINING COPOLYMER OF ETHYLENE AND VINYL ACETATE AND/OR ALKYL ACRYLATE WHEREIN THE ALKYL GROUP CONTAINS 1-18 CARBON ATOMS; ESTER OF ROSIN AND POLYHYDRIC ALCOHOLS; AND ESTER OF POLYHYDRIC ALCOHOL AND DIMER AND/OR TIMER OF FATTY ACID ARE PARTICULARLY USEFUL AS CARPET BACKING ADHESIVES.

United States Patent 3,758,431 HOT MELT COMPOSITIONS David D. Taft, 7233Monardo Lane, Minneapolis, Minn. 55435, and Terry H. Shepler, 1900Turquoise Trail, St. Paul, Minn. 55122 No Drawing. Filed June 3, 1971,Ser. No. 149,843

Int. Cl. C09j 3/26 US. Cl. 260-27 11 Claims ABSTRACT OF THE DISCLOSURERELATED CASES This application discloses and claims subject mattercommon to our copending Ser. No. 121,150 now abandoned filed on Mar. 4,1971, executed on Feb. 22, 1971 and entitled Hot Melt Compositions.

BACKGROUND OF THE INVENTION The present invention is concerned with hotmelt compositions which are especially useful as adhesives for thebacksizing of tufted carpets. More particularly the present invention isconcerned with hot melt compositions which are substantially free ofwax.

Tufted carpets are composite structures in which the yarn forming thepile, i.e., the surface of the carpet, is needled through a base fabricwhereby the base of each tuft extends through the base fabric and isvisible on the bottom surface. Tufted carpets are generally of twotypes, the first being the type commonly known as a nap carpet where theyarn loops are formed by needling or punching a continuous yarn justthrough the base fabric, thus forming the base of the carpet, while thetops of the loops are generally Azinch to inch long, thus forming thewearing surface of the carpet. The second type of tufted carpet,commonly known as a shag carpet, has the same base as the nap carpet butthe tops of the loops have been split or the tips of the loops have beencut off. The surface of the shag carpet is thus formed by the open endsof the numerous U-shaped pieces of yarn-the base of the U being embeddedin the base fabric.

The loops of yarn are needled through and embedded in the base fabric(the combination of which is the raw tufted carpet) thus forming thetufted base, which must be secured to the base fabric to prevent theloops from bein pulled out of the base fabric. The tufted bases aregenerally secured by applying an adhesive to the back of the raw tuftedcarpet to bond the tufted yarns to the base fabric. A secondary backingmaterial is usually also applied to the back of the raw tufted carpetand bonded thereto with the same adhesive that bonds the yarn to thebase fabric. The application of the secondary backing material furthersecures the loops of yarn since the loops of yarn are then bonded by theadhesive to the backing material as well as the base fabric.

The yarn used in forming the pile of a tufted carpet can be made of anytype of fiber known in the art to be useful for tufted carpets, e.g.,nylon, acrylics, wool, cotton, rayon and the like.

The base fabric or primary backing may be of any type known in the artand may be woven, for example, w0 ven jute, woven slit polypropylenefilm, burlap, and the like, or may be non-woven fabric, e.g., needle"ice punched, non-woven polypropylene web. Likewise, the secondarybacking material may be of any type known in the art, e.g., woven jute,woven slit polypropylene film, burlap, foam material such aspolyurethane foams or blown vinyl film and non-woven fabrics such asneedle punched, non-woven polyproplene web, and blends of polyesters andpolypropylene.

In preparing such tufted carpets, the adhesives are usually applied tothe primary backing which holds the tufted matrix in the form of alatex. A secondary backing is then usually applied to the carpet. Thecarpet is then heated to cure the latex to ensure a bond between thelatex and the tufted carpet, and the latex and the primary and secondarybackiugs. This curing or drying of the latex is quite time consuming,expensive, and often leads to rejects because of insufficient curingduring the process. In addition, overheating of the carpet may occurduring the curing which in turn may affect the shade of the carpet.

In addition to the use of latex as an adhesive carpet backing, recentlythere has been some activity in the use of hot melt adhesives as carpetbackings or sizing adhesives. For example, such hot melt adhesives havebeen based upon compositions containing copolymers of ethylene and vinylacetate admixed with a wax such as paraffin wax or microcrystalline wax.For example, US. Pat. 3,390,035 discloses a hot melt adhesive consistingessentially of from 90% to 10% by weight of an ethylene/ vinyl acetatecopolymer and from 90% to 10% by weight of a Wax. Such hot meltadhesives however exhibit incompatibility and sometimes separation uponcooling of the hot melt. In addition, such compositions have notdemonstrated the degree of flexibility and adhesive strength desired bythe carpet industry.

BRIEF DESCRIPTION OF INVENTION The hot melt composition of the presentinvention consists essentially of:

(A) about 10 to 50% by weight of copolymer of ethylene and vinyl acetateand/or alkyl acrylate wherein the alkyl group contains 1-18 carbonatoms, containing from 40 to 85% by weight of ethylene and from 15 to60% by weight of vinyl acetate or the 0 -0 alkyl acrylate;

(B) about 25 to 65% by weight of ester of rosin and polyhydric alcoholhaving an acid value between about 5 and 40, and a melting point betweenabout and 140 C.; and

(C) about 10 to 50% by weight of ester of polyhydric alcohol and dimerand/ or trimer of fatty acid and having an acid value of 6 to 40.

The above quantities of copolymer and esters are based upon the combinedweight of the copolymer and ester present in the composition and notnecessarily upon the total composition which may contain otheringredients.

DESCRIPTION OF PREFERRED EMBODIMENTS The hot melt composition containsfrom about 10 to 50% by weight, and preferably from about 15-35% byweight of copolymer of ethylene and an unsaturated ester which is vinylacetate or alkyl acrylate wherein the alkyl group contains 1-18 carbonatoms. The most preferred quantity of the copolymer of ethylene andunsaturated ester is about 20-30% by weight.

The copolymers to be employed in the present invention contain from 40to by weight of ethylene and from 15 to 60% by weight of vinyl acetateor C -C alkyl acrylate. Preferably the copolymer contains about 65 to82% by weight of ethylene and about 35 to 18% by weight of vinyl acetateor C -C alkyl acrylate. Generally the copolymer has a melt index of5-350. Some examples of suitable al'kyl acrylates include methylacrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexylacrylate, 2-ethylhexyl acrylate, dodecyl acrylate, lauryl acrylate andstearyl acrylate. Preferably the alkyl group of the acrylate contains1-8 carbon atoms.

The most preferred alkyl acrylates are ethyl acrylate and butylacrylate. Copolymers of ethylene and vinyl acetate and/or C C alkylacrylate are commercially available and their methods of preparation areadequately described in the literature including numerous U.S. patents.For example, the procedures described in U.S. Pat. 2,200,429 are usefulfor preparing the copolymers of ethylene used in the present invention.The ethylene copolymers can also contain about 0.001 to 15% by weight ofa comonomer such as acrylic acid, methacrylic acid, itaconic acid,acrylamide, beta dimethylaminoethyl methacrylate, beta hydroxyethylacrylate, diallyl maleate, diallyl phthalate, diallyl ether, ethyleneglycol dimethacrylate, hydroxypropyl acrylate, or hydroxypropylmethacrylate.

Some commercially available copolymers of ethylene suitable for thepurposes of the present invention are ultrathene 63 6X, which is acopolymer of 72% ethylene and 28% vinyl acetate with a melt index of 24,Ultrathene 638 which is a copolymer of 69% ethylene and 31% vinylacetate with a melt index of 24; Ultrathene 639 which is a copolymer of70% ethylene and 30% vinyl acetate with a melt index of 120; Ultrathene664 which is a copolymer of 50% ethylene and 50% vinyl acetate with amelt index of 50; Ultrathene 662 which is a copolymer of 45% ethyleneand 55% vinyl acetate with a melt index of 100; Ultrathene 633 which isa copolymer of 81% ethylene and 19% vinyl acetate with a melt index of20; CoMer EVA 501 which is a copolymer of 72% ethylene and 28% vinylacetate with a melt index of 350; CoMer EVA 505 which is a copolymer of72% ethylene and 28% vinyl acetate with a melt index of 20; CoMer EVA605 which is a copolymer of 67% ethylene and 33% vinyl acetate with amelt index of 20; Elvax 150 which is a copolymer of 67% ethylene and 33%vinyl acetate with a melt index of 25; Elvax 240 which is a copolymer of72% ethylene and 28% vinyl acetate with a melt index of 22-28; Elvax 250which is a copolymer of 72% ethylene and 28% vinyl acetate with a meltindex of 12-18; Elvax 350 which is a copolymer of 75% ethylene and 25%vinyl acetate with a melt index of 16-22, Elvax 40 which is a copolymerof 60% ethylene and 40% vinyl acetate with a melt index of 45 to 70;CoMer DPDA-9l69 which is a copolymer of 82% ethylene and 18% ethylacrylate with a melt index of 20; and the Zetafax resins which arecopolymers of ethylene and butyl acrylate. The Ultrathene polymers areavailable from USI, the CoMer polymers from Union Carbide, the Elvaxpolymers from Du Pont and the Zetafax polymers from Dow Chemical.

The composition also contains from about 25 to 65% by weight andpreferably about 3555% by weight and most preferably about 40-50% byweight of ester of rosin and polyhydric alcohol. The ester has an acidvalue between about and 40 and most preferably between about and 20, anda melting point range between about 75 and 140 C., and preferablybetween about 90 and 115 C.

The most preferred melting point is between about 90 and 100 C. Thepolyhydric alcohol used in forming this ester generally contains from 2to 6 alcohol groups and is a saturated aliphatic compound.

Some suitable dihydric alcohols include among others the lower glycolssuch as ethylene glycol, 1,2-propanediol, 1,3-propanediol, diethyleneglycol, triethylene glycol, tetraethylene glycol, hexamethylene glycol,1,3-butanediol, 1,4-butanediol, and 2,3-butanediol. Some suitablealcohols which contain from 3 to 6 alcohol groups include glycerol,trimethylol propane, trimethylolethane, pentaerythritol, and hexitols,such as mannitol and b to Of course, mixtures of alcohols may beemployed in preparing this ester. One such mixture is Sutro 250 which isavailable from Atlas Chemical Industries, Inc., and is a mixture ofessentially straight-chain polyhydric alcohols of 3 to 6 carbon atoms.Sutro 250 and other Sutro polyhydric alcohols are described inIndustrial Polyol Bulletin LG-93 Rev. 4M-l1/ 66, Sutro Polyols, AtlasChemical Industries, Inc., Chemicals Division, Wilmington, Del., 19899,which is incorporated herein by reference.

The preferred polyhydric alcohol is pentaerythritol. The rosin employedis generally a wood or tall oil rosin.

The ester may be prepared, for instance, by reacting parts of the rosinand about 6 to 15 parts by weight of the alcohol such as pentaerythritolin the presence of a metallic catalyst at elevated temperature ofZOO-250 C. until the desired acid value is reached.

The hot melt composition also contains from about 10 to 50%, preferablyabout 2045%, and more preferably about 2535% by weight of ester ofpolyhydric alcohol and dimer and/or trimer of aliphatic ethylenicallyunsaturated monocarboxylic fatty acid having 16-22 carbon atoms.Correspondingly, the dimer contains 32-44 carbon atoms and the trimercontains 48-66 carbon atoms. The preferred dimers and trimers are thedimers and trimers of oleic acid and/or linoleic acid. The mostpreferred dimers and trimers are the dimers and trimers of tall oilfatty acids.

Also the dimer and/or trimer may be employed as a mixture with suchother materials as monomeric aliphatic ethylenically unsaturatedmonocarboxylic fatty acids having 16-22 carbon atoms, polymeric forms ofthe monomeric aliphatic ethylenically unsaturated monocarboxylic fattyacids higher than trimer, rosin acids, and dimerized rosin. Preferablythe dimer and/or trimer is employed as a mixture with rosin acids anddimerized rosin. When employing a mixture it should contain at least 20%by weight of the dimer and/or trimer and/or higher polymers of theacids. Such mixtures are commercially available. Of particularimportance is Emtall 664 available from Emery Industries, Inc.,Cincinnati, Ohio. This mixture according to Emery contains about 2530%by weight of dimer and/or higher polymers of tall oil fatty acids andabout 4055% by Weight of rosin acids. The rosin acids include bothmonomeric and polymeric forms of the acid. The remainder is fatty acidshaving an average chain length of about 18 carbon atoms or higher, andunsaponifiables. Another commercially available material is Fatty Acid7002 available from Arizona Chemical. This mixture contains about 45% byweight of dimerized tall oil fatty acids, 25% by weight of trimer izedand higher polymers of tall oil fatty acids, 6% of C fatty acids, 13% ofrosin acids, 2% of unsaponifiables, and 7% of C fatty acids. Inaddition, conventionally supplied pure dimer or trimer acids or mixturesthereof may be employed in the preparation of this ester. The polyhydricalcohol used in forming this ester generally contains from 2 to 6alcohol groups.

Some suitable dihydric alcohols include among others the lower glycolssuch as ethylene glycol, 1,2-propanediol, 1,3-propanediol, diethyleneglycol, triethylene glycol, tetraethylene glycol, hexamethylene glycol,1,3- butanediol, 1,4-butanediol, and 2,3-butanediol. Some suitablealcohols which contain from 3 to 6 alcohol groups include glycerol,trimethylolpropane, trimethylolethane, pentaerythritol,dipentaerythritol, and hexitols, such as mannitol and sorbitol. Ofcourse, mixtures of alcohols of the above as well as Sutro 250 may beemployed in preparing this ester.

The preferred polyhydric alcohols contain from 3-6 alcohol groups. Themost preferred polyhydric alcohols are glycerine and pentaerythritol.This ester should have an acid value between about 8 and 40, andpreferably between 10 and 25 and a viscosity of between about 1.0 to40.0 stokes, preferably 2.020.0 stokes, as measured in mineral spiritsat a 70% non-volatile concentration.

This ester can be prepared by reacting the dimer and/or trimer ormixture containing the dimer and/or trimer with the polyhydric alcoholunder esterification conditions, e.g., ZOO-250 C., until the desiredacid value is obtained. For instance, the desired ester can be preparedby reacting about 100 parts by weight of the dimer and/ or trimer andabout 5 to 35 parts by weight of polyhydric alcohol, such aspentaerythritol, in the presence of a calcium acetate catalyst. Thereaction mixture is heated to 400 F. and held at that temperature for 1hour. After this the temperature is raised to between about 480 andabout 500 F. and is held there until the reaction is complete asevidenced by a product having an acid value and viscosity within thedesired ranges. The mixture is usually held at the 480 to 500 F.temperature range for about -15 hours. If desired, the reaction time canbe reduced by carrying the reaction out under a partial vacuum of aboutto inches of Hg. Similarly this dimer and/ or trimer ester can beprepared together with the ester of rosin and polyhydric alcohol byadding the dimer and/ or trimer, the rosin and polyhydric alcoholtogether and esterifying.

The various quantities set forth above for the ethylene copolymer, therosin ester and the dimer and/or trimer ester are based upon thecombined weight of these components and not necessarily upon the totalcomposition which may include other ingredients.

The melting point of the ingredients in this invention is a softeningpoint which is determined by a modified mercury drop method.

The hot melt composition of the present invention contains up to about70% by Weight of a solid filler material based upon the totalcomposition. Preferably the composition contains between about 40 and60% by weight of the solid filler material based upon the totalcomposition. Some suitable solid fillers are calcium carbonate, clay,and talc. Calcium carbonate is the preferred filler. One feature of thepresent invention is the ability to incorporate such large quantities ofsolid filler material into the composition without detracting from thecoating properties of the composition to such an extent as to render thecomposition unsuitable for its intended purpose. Flame retardant fillersmay also be employed to improve the flame retardant properties of thecarpet. Such fillers are sold under the trade designation of Phosgardobtainable from Monsanto and Firmaster obtainable from MichiganChemical.

The composition of the present invention may also contain up to about 2%by weight and preferably from about 0.1 to 1% by weight of anantioxidant based upon the total composition. Some suitable antioxidantsinclude 2,2 methylene bis (-4-methyl-6-tert.butylphenol),2,4,6-tritert.butylphenol, 2,6 di tert.butyl-4-methylphenol, 4,4thio-bis (-6-tert.butyl-m-cresol), butylated hydroxy anisole, andbutylated hydroxy toluene. The preferred antioxidant is 2,2 -methylenebis (-4-methyl-6-tert.butylphen- 01).

The hot melt compositions of the present invention provide excellentadhesion between the pile loops and the primary backing and between thesecondary backing and the carpet. This excellent adhesion can beobserved from the force in pounds required to pull one of the pile loopsloose from the primary backing and from the amount of force in poundsrequired to separate the secondary backing from the carpet.

In addition the compositions exhibit surprisingly high flexibility,elongation and tensile properties.- Also the hot melts of the presentinvention are surprisingly soft as compared to ethylene/vinyl acetatecopolymer compositions containing wax, thus facilitating the coatingprocedure. Moreover the compositions of the present invention are lesslikely to support combustion than are various wax containing hot meltcompositions. Therefore, they are much safer to use.

Unlike the wax containing hot melt compositions, the

present compositions are quite compatible and are not opaque at elevatedtemperatures. This high compatibility between the components of thepresent invention greatly diminishes the problem of possible separationof the components of the composition after they have been applied to thesubstrate and are allowed to age. In addition, the excellent propertiesof the present compositions are readily reproducible from batch tobatch. In the wax containing hot melt compositions however it is quitedifiicult to reproduce a uniform product in that small changes in themelting point of the wax drastically vary the coating characteristics ofthe composition.

Surprisingly, the compositions of the present invention demonstratetheir excellent adhesion properties when applied to polyolefinsubstrates such as polyethylene and polypropylene. Polyolefin fibersand/ or secondary backings have not been commercially employed to theextent desired because of the difiiculty in finding adhesivecompositions suitable for adhering these substrates to other substratesor to each other. The present compositions however surprisingly areexcellent adhesives for these polyolefin substrates.

The hot melt compositions of the present invention can be prepared byany of the conventional means by which two or more ingredients arebrought into intimate contact with each other. For example, the ester ofthe polyhydric alcohol and rosin; the ester of the polyhydric alcoholand the dimer and/or trimer; and the antioxidant, if used, are added toa mixing vessel which is blanketed in a nitrogen atmosphere. The mixtureis then heated to about 350 F. The copolymer of ethylene and vinylacetate and/or C -C alkyl acrylate is then slowly added with stirring tothe heated mixture. The stirring is continued at this temperature untila clear melt forms. The filler, if used, can then be added to themixture slowly with stirring until thoroughly dispersed therein. Themolten nuxture can then be pumped directly to a carpet coating apparatusor can be cooled for storage and used at some later time.

The composition of the present invention can be applied to theparticular substrate by any of the well known methods of applyingcoatings of molten adhesives. For example, the hot melt coating can beapplied by extrusion, a heated doctor blade, or by passing the bottomsurface of the tufted material in contact with the top surface of arotating roller partially submerged in a tank of the molten adhesive. Itis convenient to employ a doctor blade in order to control the thicknessof the adhesive on the roller.

The carpets prepared according to the present invention are usefulwherever carpets are used, for example, on floors and on stairways inhomes, restaurants, hotels, office buildings, and in passenger sectionsof ships, trains, airplanes, and automobiles.

The composition is applied to the carpet in amounts ranging from about 6to about 40 ounces per square yard of carpet and preferably from about12-28 ounces per square yard and at a temperature of about 160 F. and375 F. It is, of course, understood that the temperature must bemaintained so that melting or decomposition of the textile backings andfibers do not occur, and must be substantially above the melting pointof the coating composition. From about 15 to feet of carpet per minutecan be coated with the composition of the present invention.

In order to better understand the present invention, the followingexamples are given in which all quantities are by weight unless thecontrary is set forth:

EXAMPLE A Preparation of ester of rosin and pentaerythritol 910 parts oftall oil rosin, parts of pentaerythritol, and 0.5 part of oxalic acidare charged to a reactor and heated to 250 C. The reactor is fitted foresterification.

7 The reaction is continued until an acid value of 35 is reached. Vacuumis then applied until the acid value is less than 20. The material iscooled to 200 C. and filtered into a cooling pan. The ester has an acidvalue of 7.5, a viscosity of 1.2 stokes in toluene at 70% non-volatiles,and a Gardner color of 12+.

EXAMPLE B Preparation of ester of Emtall 664 and Sutro 250 325 parts ofEmtall 664 and 47 parts of Sutro 250 are charged to a reactor fitted foresterification and heated to 400 F. The reaction is continued for 3hours until an acid value of 12.4 is reached. The material is cooled toroom temperature for use in the hot melt compositions.

EXAMPLE C Preparation of ester of pentaerythritol and mixture containingdimerized tall oil fatty acids 936 parts of Emtall 664, 114 parts ofpentaerythritol, and 0.17 part of a calcium acetate catalyst are chargedto a reactor which is blanketed in a nitrogen atmosphere. The reactionmixture is then heated to 200 C. and held at that temperature for 1hour. The temperature is then raised to between about 250 C. and about271 C. and is held there for about 15 hours, at which time the reactionis complete. The ester has an acid value of 12-18, a viscosity of 2.54.0stokes in mineral spirits at 70% non-volatiles, and a Gardner color of9-12.

EXAMPLE D Preparation of ester of pentaerythritol, ethylene glycol, andmixture containing dimerized and trimerized tall oil fatty acids 1500parts of fatty acids 7002, 90 parts of pentaerythritol, and 47 parts ofethylene glycol are charged to a reaction vessel fitted foresterification. The reaction mixture is heated to 365 F. wheer waterbegins to distill and then to 465-485 F. over a period of 45 hours. Thereaction mixture is cooled slowly to room temperature. The ester has anacid value of 24 and a viscosity of 19.0 stokes in mineral spirits at70% non-volatiles.

EXAMPLE E Preparation of ester of glycerine and mixture containingdimerized and trimerized tall oil fatty acids 1500 parts of fatty acids7002 and 132.8 parts glycerine are charged to a reaction vessel which isblanketed in a nitrogen atmosphere. The reaction mixture is then heatedto 440'460 F. and held at that temperature for 3-4 hours. The reactionproduct has an acid value of 17.2, a viscosity of 9.0 stokes in mineralspirits at 70% non-volatiles, a color of 13+.

EXAMPLE 1 The raw tufted carpet is a shag carpet composed of a jute basefabric weighing about ounces/yard and tufted with about 14 ounces/yardof bulked continous filament nylon carpet yarn which is needled into thebase fabric at 6 needles per inch across the width of the base fabricand about 6 stitches per running inch of base fabric. The tuft loopsextend 1% inch above the base fabric and the tufted bases extent inchbelow the base fabric. The secondary backing material is wovenpolypropylene weighing about 3.5 ounces/yard? The raw tufted carpet ispassed under and adjacent to an extruder where the bottom (non-pile)surface is coated with about 24 ounces/yard of a molten coatingcomposition at a temperature of 350 F. and having the following formula:

Parts Copolymer of 67% ethylene and 33% vinyl acetate, having aninherent viscosity of 0.74 (0.25%) in toluene at 86 F.), a melt index of20 (ASTM- Dl238577), and a softening point of 220 F.

(ring and ball) (CoMer 605) 12.0 Ester from Example A 24.0 Ester formExample C 13.8 2,2'-methylene bis-(4-methyl-6-tert.butylphenol) 0.2 CaCO(#1 White) 50.0

The molten composition which is kept at 350 F. is forced through theextruder head onto the back of the raw tufted carpet as it passes by theextruder head. The carpet then passes underneath a heated doctor bladewhich evenly distributes any excess adhesive that may be present. Thecarpet then passes between two rollers at which point the secondarybacking material from the upper roll is applied to the back side of thecarpet. The carpet is then passed into a forced-air cooling section 10feet in length to set the coating composition. The primary backing ofjute and the secondary backing material are firmly bonded to each other,and the base of each loop in the pile is firmly bonded to the primarybacking. A pull of 26 pounds is required to pull one of the pile loopsloose from the primary backing. The carpet has a T peel of about 25-27pounds. In addition the carpet demonstrated excellent resistance todelamination when subjected to repeated bending and straightening.

In addition the percent elongation of a 40 mil film of the compositionis greater than 600 percent as measured on an Instron Tensile Tester.

EXAMPLE 2 Example 1 is repeated except that the coating composition hasthe following formula:

Parts Copolymer of 72% ethylene and 28% vinyl acetate, having aninherent viscosity of .54 (0.25% in toluene at 86 F.), a melt index of350 (ASTM- D-1238-577) and a softening point of F (ring and ball) (CoMerEVA 501) 2.0 Copolymer of 67% ethylene and 33% vinyl acetate, having aninherent viscosity of .74 (0.25% in toluene at 86 F.), a melt index of20 (ASTM- D-1238-577) and a softening point of 220 F. (ring and ball)(CoMer EVA 605 1.0 Copolymer of 82% ethylene and 18% ethyl acrylatehaving an inherent viscosity of .81 (0.25% in toluene at 86 F.), a meltindex of 51 (ASTM- D-l238-577) and a softening point of 307 F.) (ringand ball) CoMer DPD 9169) 9.0 Ester from Example A 24.0 Ester fromExample C 13.8 2,2-rnethylene bis (-4-methyl-6-tert.butylphenol) 0.2CoCo (#1 White) 50.0

The primary backing of jute and the secondary backing of polypropyleneare firmly bonded to each other, and the base of each loop in the pileis firmly bnded to the primary backing. A pull of 32 pounds is requiredto pull one of the pile loops loose from the primary backing. The carpethas a T peel of about 20-23 pounds. In addition the carpet demonstratesexcellent resistance to delamination when subjected to repeated bendingand straightening.

In addition the percent elongation of a 40 mil film of the coatingcomposition is greater than 600 percent as measured on an InstronTensile Tester.

9 EXAMPLE 3 Example 1 is repeated except that the coating compositionhas the following formula:

Parts Copolymer of 67% ethylene and 33% vinyl acetate,

having an inherent viscosity of .78 (0.25% in toluene at 86 F.), a meltindex of 250 (ASTM-D- 1238-577), and a softening point of 240 F. (ringand ball) (Elv-ax 150) 12.0 Ester from Example A 22.0 Ester from ExampleC 13.4 2,2'-methylene bis (-4-methyl-6-tert.butylphenol) 0.4

CaCO (#1 White) 52.2

The primary backing of jute and the secondary backing of polypropyleneare firmly bonded to each other, and the base of each loop in the pileis firmly bonded to the primary backing. A pull of 2025 pounds isrequired to pull one of the pile loops loose from the primary backing.The carpet has a T peel of about 25 pounds. In addition the carpetdemonstrated excellent resistance to delamination when subjected torepeated bending and straightening.

EXAMPLE 4 Example 1 is repeated except that the coating composition hasthe following formula:

Parts Copolymer of 72% ethylene and 28% vinyl acetate, having aninherent viscosity of .86 (0.25% in toluene at 86 F.), a melt index of24 (ASTMD1238577), and a softening point of 242 F. (ring and ball)(Ultrathene 636) 24.9 Ester from Example A 46.3 Ester from Example C28.1 2,2-methylene bis (-4-methyl-6-tert.butylphenol) 0.7 CaCO (#1White) 100.0

The primary and secondary backing of jute materials are firmly bonded toeach other, and the base of each loop in the pile is firmly bonded tothe primary backing. A pull of 20-25 pounds is required to pull one ofthe pile loops loose from the primary backing. The carpet has a T peelof about 20 pounds. In addition the carpet demonstrated excellentresistance to delamination when subjected to repeated bending andstraightening.

EXAMPLE 5 Example 1 is repeated except that the coating composition hasthe following formula:

The primary backing of jute and the secondary backing of polypropyleneare firmly bonded to each other, and the base of each loop in the pileis firmly bonded to the primary backing. A pull of 25 ponuds is requiredto pull one of the pile loops loose from the primary backing. The carpethas a T peel of about 20 pounds. In addition the carpet demonstratedexcellent resistance to delamination when subjected to repeated bendingand straightenmg.

In addition the percent elongation of a 40mil film of the coatingcomposition is greater than 630 percent as measured on an InstronTensile Tester.

10 EXAMPLE 6 Example 1 is repeated except that the secondary backingmaterial is jute weighing about 10 ounces/yard The primary and secondarybacking materials are firmly bonded to each other, and the base of eachloop in the pile is firmly bonded to the primary backing. The carpet hasa T peel of more than 50 pounds. In addition the carpet demonstratedexcellent resistance to lamination when subjected to repeated bendingand straightening.

EXAMPLE 7 Example 2 is repeated except that the secondary backingmaterial is jute weighing about 10 ounces/yard The primary and secondarybacking materials are firmly bonded to each other, and the base of eachloop in the pile is firmly bonded to the primary backing. The carpet hasa T peel of about 50 seconds. In addition the carpet demonstratedexcellent resistance to delamination when subjected to repeated bendingand straightening.

EXAMPLE 8 Example 1 is repeated except that the secondary backingmaterial is non-woven polyester/polypropylene weighing about 4.2ounces/yard The primary and secondary backing materials are firmlybonded to each other, and the base of each loop in the pile is firmlybonded to the primary backing. The carpet has a T peel of about 25-30pounds. In addition the carpet demonstrated excellent resistance todelamination when subjected to repeated bending and straightening.

EXAMPLE 9 Example 2 is repeated except that the secondary backing isnon-woven polyester-polypropylene weighing about 4.2 ounces/yard Theprimary and secondary backing materials are firmly bonded to each other,and the base of each loop in the pile is firmly bonded to the primarybacking. The carpet has a T peel of about 18-20 pounds. In addition thecarpet demonstrated excellent resistance to delamination when subjectedto repeated bending and straightening.

EXAMPLE 10 Example 3 is repeated except that the secondary backingmaterial is jute weighing about 10 ounces/yard The primary and secondarybacking materials are firmly bonded to each other, and the base of eachloop in the pile is firmly bonded to the primary backing. The carpet hasa T peel of about 25-30 pounds. In addition the carpet demonstratedexcellent resistance to delamination when subjected to repeated bendingand straightening.

EXAMPLE 11 Example 3 is repeated except that the secondary backingmaterial is non-woven polyester/polypropylene weighing about 4.2ounces/yard The primary and secondary backing materials are firmlybonded to each other, and the base of each loop in the pile is firmlybonded to the primary backing. The carpet has a T peel of about 30seconds. In addition the carpet demonstrated excellent resistance todelamination when subjected to repeated bending and straightening.

EXAMPLE 12 Example 4 is repeated except that the secondary backing isnon-woven polyester/ polypropylene weighing about 4.2 ounces/yard Theprimary and secondary backing materials are firmly bonded to each other,and the base of each loop in the pile is firmly bonded to the primarybacking. The carpet has a T peel of about 45 pounds. In addition thecarpet demonstrated excellent resistance to delamination when subjectedto repeated bending and straightening.

1 1 EXAMPLE 13 Example 4 is repeated except that the secondary backingmaterial is jute weighing about 10 ounces/yard The primary and secondarybacking materials are firmly bonded to each other, and the base of eachloop in the pile is firmly bonded to the primary backing. The carpet hasa T peel of about 25-35 pounds. In addition the carpet demonstratedexcellent resistance to delamination when subjected to repeated bendingand straightening.

EXAMPLE 14 EXAMPLE 15 Example is repeated except that the secondarybacking material is jute weighing about ounces/yard? The primary andsecondary backing materials are firmly bonded to each other, and thebase of each loop in the pile is firmly bonded to the primary backing.The carpet has a T peel of greater than 30 pounds. In addition carpetdemonstrated excellent resistance to delamination when subjected torepeated bending and straightening.

COMPARISON EXAMPLE 16 Example 1 is repeated except that the coatingcomposition has the following formula:

Parts Copolymer of 67% ethylene and 33% vinyl acetate having an inherentviscosity of .78 (0.25% in toluene at 86 F.), a melt index of 25 (ASTM-D-1238-577) and a softening point of 240 F.

(ring and ball) (ELVAX 150) 14.0 Rosin WW (available from Tenneco) 30.6Polypale (available from Picco) 8.2 2,2'-methylene bis(-4-methyl-6-tert.butylphenol) 0.2 CaCO (#1 White) t 30.0 Wax--ParaflintRG Fisher-Tropsch wax having a melting point of 215 F 17.0

A pull of 18 pounds is required to pull one of the pile loops loose fromthe primary backing. The carpet has a T peel of about 1.5 pounds. Thecarpet demonstrated considerable delamination when subjected to repeatedbending and straightening. The percent elongation of a 40 mil film ofthe coating composition is only 30.

COMPARISON EXAMPLE 17 Example 1 is repeated except that the coatingcomposition has the following formula:

Parts Copolymer of 67% ethylene and 33% vinyl acetate having an inherentviscosity of .78 (0.25 in toluene at 86 :F.), a melt index of 25 (ASTM-D-1238-577) and a softening point of 240 F.

(ring and ball) (ELVAX 150) 14.0 Rosin WW (available from Tenneco) 38.32,2-methylene bis (-4-methyl-6-tert.butylphenol) 0.3 Barium sulfate 30.0WaxParaflint RG Fisher-Tropsch wax having a melting point of 215 F. 17.4

A pull of 23 pounds is required to pull one of the pile loops loose fromthe primary backing. The carpet has a T peel of about 3.5 pounds. Thecarpet demonstrated considerable delamination when subjected to repeatedbending and straightening. The percent elongation of a 40 mil film ofthe coating composition is only 200.

12 COMPARISON EXAMPLE. 18

Example 1 is repeated except that the coating composition has thefollowing formula:

Parts Copolymer of 72% ethylene and 28% vinyl acetate having an inherentviscosity of .85 (0.25% in toluene at 86 F.), a melt index of 15 (ASTMD1238577) and a softening point of 28 F.

(ring and ball) (ELVAX 250) 17.5 Rosin WW (available from Tenneco) 40.82,2-methylene bis (-4-methyl-6-tert.butylphenol) 0.2 CaCO;. (#1 White)30.0 Wax--Paraflint RG Fisher-Tropsch wax having a melting point of 215F 11.5

A pull of 25 pounds is required to pull one of the pile loops loose fromthe primary backing. The carpet has a T peel of about 3.5 pounds. Thecarpet demonstrated considerable delamination when subjected to repeatedbending and straightening. The percent elongation of a 40 mil film ofthe coating composition is 365.

COMPARISON EXAMPLE 19 Example 1 is repeated except that the coatingcomposition has the following formula:

Parts Copolymer of 67% ethylene and 33% vinyl acetate having an inherentviscosity of .78 (0.25% in toluene at 86 F.), a melt index of 22-28(ASTM-D-l238-577) and a softening point of of 240 F. (ring and ball)(ELVAX 10.0 Rosin WW (available from Tenneco) 21.8 Polypale (availablefrom Picco) 5.9 2,2'-methylene bis (-4-methyl-6-tert.butylphenol) 0.2CaCO (#1 White) 50.0 Wax-Paraflint RC Fisher-Tropsch wax having amelting point of 215 F. 12.1

A pull of 25 pounds is required to pull one of the pile loops loose fromthe primary backing. The carpet has a T peel of about 2 pounds. Thecarpet demonstrated considerable delamination when subjected to repeatedbending and straightening. The percent elongation of a 40 mil film ofthe coating composition is 40.

COMPARISON EXAMPLE 20 Example 16 is repeated except that the secondarybacking is jute weighing about 10 ounces/yard The carpet has a T peel ofabout 30 pounds. The carpet demonstrated considerable delamination whensubjected to repeated bending and straightening.

COMPARISON EXAMPLE 21 Example 17 is repeated except that the secondarybacking is jute weighing about 10 ounces/yard The carpet has a T peel ofabout 8 pounds. In addition the carpet demonstrated considerabledelamination when subjected to repeated bending and straightening.

COMPARISON EXAMPLE 22 Example 18 is repeated except that the secondarybacking is jute weighing about 10 ounces/yard The carpet has a T peel ofabout 25 pounds. In addition the carpet demonstrated considerabledelamination when subjected to repeated bending and straightening.

COMPARISON EXAMPLE 23 Example 19 is repeated except that the secondarybacking is jute weighing about 10 ounces/yard? The carpet has a T peelof about 23 pounds. In addition the carpet demonstrated considerabledelamination when subjected to repeated bending and straightening.

13 COMPARISON EXAMPLE 24 Example 16 is repeated except that thesecondary backing is non-woven polyester/ polypropylene weighing about44.2 ounces/yard The carpet has a T peel of about 6.5 pounds. Inaddition the carpet demonstrated considerable delamina tion whensubjected to repeated bending and straightening.

COMPARISON EXAMPLE 25 Example 17 is repeated except that the secondarybacking is non-woven polyester-polypropylene weighing about 4.2ounces/yard The carpet has a T peel of about 7 pounds. In addition thecarpet demonstrates considerable delamination when subjected to repeatedbending and straightening.

COMPARISON EXAMPLE 26 Example 18 is repeated except that the secondarybacking is non-woven polyester-polypropylene weighing about 4.2ounces/yard The carpet has a T pee of about pounds. In addition thecarpet demonstrated considerable delamination when subjected to repeatedbending and straightenin COMPARISON EXAMPLE 27 Example 19 is repeatedexcept that the secondary backing is non-woven polyester-polypropyleneweighing about 4.2 ounces/yard? The carpet has a T peel of about 4pounds. In addition the carpet demonstrated considerable delaminationwhen subjected to repeated bending and straightening.

The pull required to pull one of the pile loops loose from the primarybacking is determined by attaching a sample of the carpet to a Chatillontension tester. The pile is pulled at 12"/min. until it pulls out andthe value in pounds is recorded from the tester. The above procedure isrepeated five more times and the average of the six tests is used as thevalue.

The T-Peel is determined by attaching a sample of the carpet havingabout 4 inches of laminated surface in an Instron Tensile Tester andpulling at 12"/min. the sample apart at an angle of 180".

A comparison of Examples 1-15 with 16-27 clearly establishes that thecompositions of the present invention possess unexpectedly excellentadhesive properties, particularly when applied to a polyolefincontaining substrate.

What is claimed is:

1. A hot melt composition consisting essentially of:

(A) copolymer of ethylene and unsaturated ester monomer selected fromthe group consisting of vinyl acetate, alkyl acrylate wherein the alkylgroup contains 1-18 carbon atoms, and mixtures thereof, containing from40-85% by weight of ethylene and from -60% by weight of said unsaturatedester monomer;

(B) ester of rosin and polyhydric alcohol, wherein the 14 ester has anacid value between about 5 and 40, and melting point range between 75and 140 C.; and

(C) ester of polyhydric alcohol and dimer and/or trimer or mixturethereof, of aliphatic ethylenically unsaturated monocarboxylic fattyacid having 16-22 carbon atoms, wherein said ester has an acid value of6 to 40; and wherein said composition based on the combined weight of(A), (B), and (C) contains about 10-50% by weight of (A); about 25-65%by weight of (B); and about 10- 50% of (C).

2. The composition of claim '1 wherein said copolymer is a copolymer ofethylene and vinyl acetate which contains from about to 82% by weight ofethylene and from 35 to 18% by weight of vinyl acetate.

3. The composition of claim 1 wherein said ester of rosin and polyhydricalcohol is the reaction product of rosin and pentaerythritol.

4. The composition of claim 1 wherein said ester of polyhydric alcoholand dimer, trimer or mixture thereof is ester of pentaerythritol andwherein said dimer, trimer, or mixture thereof is dimer, trimer ormixture thereof of tall oil fatty acids.

5. The composition of claim 1 which also contains up to about by weightof filler.

6. The composition of claim 1 which also contains up to about 2% byweight of antioxidant.

7. The composition of claim 1 wherein said copolymer of ethylene ispresent in an amount from about 15 to about 35% by weight based upon thecombined weight of (A), (B) and (C).

8. The composition of claim 5 wherein said filler is present in anamount from about 40 to about 60% by weight.

9. The composition of claim 6 wherein said antioxidant is present in anamount from 0.1 to 1.0% by weight.

10. The composition of claim 8 wherein said filler is calcium carbonate.

11. The composition of claim 9 wherein said antioxidant is2,2'-methylene bis-(-6-tert.butyl-4-methylphenol).

References Cited UNITED STATES PATENTS 3,615,106 10/1971 Flanagan 260-27EV 3,492,258 1/ 1970 Kremer 2-60--27 EV FOREIGN PATENTS 708,663 4/1965Canada 260-27 EV 721,439 11/1965 Canada 26027 EV DONALD E. CZAJA,Primary Examiner W. E. PARKER, Assistant Examiner U.S. Cl. X.R.

